Heat domes! Derechos! Haboobs! Stay prepared for wild weather with this new climate cheat sheet.
You’re watching the weather report and hear there’s a bomb cyclone or derecho headed your way. Say what?! With all the weird new weather terms out there, it’s like you need a translator to understand the daily forecast.
As the weather gets more unpredictable, these lesser-known weather events and terms are becoming increasingly common, says Jacob Hinson, a meteorologist with AccuWeather in State College, Pennsylvania. “Climate change can lead to more extreme weather,” he explains. “So it’s essential to stay up to date on the new terms that have popped up because they make it easier to classify what’s actually happening now.”
Knowing the latest lingo not only helps you know how to dress and whether to grab an umbrella, but it also ensures you’ll be prepared for whatever conditions are rolling in. “We experience weather every single day,” Hinson says, “so it’s very important for our health and safety to know what’s going on, especially as we start to experience the more intense weather impact.”
So with that in mind, we asked Hinson and Baker Perry, PhD, professor of climatology at the University of Nevada, Reno, to share the terms you need to know now—and what they mean for your life.
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Lesser-known weather terms
Ready to go beyond partly cloudy and snowstorm? These are the trending climate phrases you’ll want to master to be ready for whatever system is brewing near you.
Derecho
A derecho is “an intense and long-lived windstorm,” Hinson says. The winds are straight, and that’s where it gets its name. Derecho is Spanish for “right,” “straight” or “direct,” according to the National Oceanic and Atmospheric Administration (NOAA). Contrast that to a tornado, which comes from tornar and means “to turn” in Spanish.
To be classified as a derecho, a windstorm must have winds of at least 58 mph, some gusts over 75 mph and a wind damage path of at least 250 miles long. These severe storms can produce damaging winds over hundreds of miles long and more than 100 miles across.
If you hear a derecho is heading your way, avoid outdoor activities and stay off the roads if you can, as the winds can overturn cars. NOAA warns against boating and hiking too, because high winds and waves can flip boats and topple trees.
Flash drought
A flash drought is a very rapid onset or intensification of drought, Perry says. This challenging pattern occurs where there’s low rainfall paired with high temperatures, high winds and/or high radiation. A flash drought can be devastating for agriculture and ecosystems. “Soil and vegetation are particularly sensitive to rapid water loss and substantial damage,” Perry notes.
Fascinating fact: The term flash drought isn’t that old. It was coined in the early aughts by climatologist Mark Svoboda, PhD, director of the National Drought Mitigation Center at the University of Nebraska–Lincoln. He came up with the expression on the fly while trying to explain to a reporter the fast-developing droughts hitting the Plains at the time (which are still wreaking havoc today).
Haboob
A haboob is a massive dust storm that gets kicked up by thunderstorms, typically in the Southwest. “You’ll see them a lot in Arizona, especially during the monsoon season, which is late summer to early fall,” Hinson says. “They bring potentially dangerous conditions because you have reduced visibility.” You may remember back in August when Phoenix was hit with a big haboob that left parts of the city with almost zero visibility.
“They generate some pretty stunning imagery,” Hinson notes. But don’t stick around outside trying to snap the perfect shot. Heed the advice the National Weather Service in Phoenix posted on X in August: Pull aside, stay alive.
Heat dome
Heat dome could have been the climate phrase of the summer, with dangerous heatwaves gripping the country (August 2025 was the fourth-hottest month on record in the U.S., per the National Centers for Environmental Education). “A heat dome is basically heat getting trapped under high pressure,” Hinson explains. “It’s a phenomenon related to jet-stream patterns that cause sweltering weather to get locked in.”
The high heat can stay trapped that way for weeks, which is no fun for us. If you don’t remember growing up with heat domes, that’s because they are way more common now. A 2025 study by University of Pennsylvania researchers found that heat domes—and certain other forms of extreme weather—have tripled in the past 50 years.
Mudflow
A mudflow is “similar to a landslide, but with much more water,” says Perry. The water is mixed with dirt and debris, but it’s not sludgy. It’s more like the consistency of pancake batter, per the Colorado Geological Society.
So what’s the difference between a mudflow and a mudslide? In a mudflow, more than half of the particles are the size of sand or smaller. A mudflow may sound like just another muddy mess, but make no mistake: Mudflows and landslides can be quite dangerous. These weather-related events kill 25 to 50 people in the U.S. each year, according to the U.S. Centers for Disease Control and Prevention (CDC).
Nor’easter
If you’ve ever battled New England winters, you’ve surely experienced the joy of a nor’easter. But you might not know what separates a nor’easter from an ordinary winter storm. A nor’easter is a low-pressure storm with winds out of the northeast. In fact, that’s where it gets its name—it has nothing to do with the fact that it mainly strikes the Northeast. (That’s just one of those weather myths that won’t go away.)
A nor’easter is a wallop of a wintery mix, dumping heavy rain or snow and gale-force winds that often lead to coastal damage. They generally start along the Southeastern coast and intensify as they move up the coast. While nor’easters aren’t getting more common, they are becoming more intense, according to a 2025 study out of the University of Pennsylvania.
Pineapple express
Less fun than it sounds, a pineapple express is a type of atmospheric river that sends water vapor in the sky from Hawaii to the West Coast and blasts the region with heavy rain and snow. When a pineapple express hits California or the Pacific Northwest, as it did in February 2025, there can be flooding, mudslides and other treacherous conditions.
Polar vortex
The polar vortex is one of those weather terms you’ve heard before but may not know precisely what it describes. It’s a low-pressure pool of cold air in the Arctic that is usually kept in place by the jet stream—but sometimes sends bursts of frigid air to the U.S. Remember the chilly start to 2025 that hit many parts of the country? That was the polar vortex in action, according to NOAA.
Insider tip: If you hear the polar vortex is “weak” or “weakening,” don’t celebrate. In that context, “weak” means the low-pressure system is wobbly, which can allow frigid air to break off and come down to torment us.
Scud clouds
They may sound like missiles, but in weather parlance, scuds are low-lying cloud fragments that can be found around thunderstorms. They’re harmless, but since they’re low to the ground and rather ominous looking, scud clouds often get mistaken for tornadoes—which are definitely not harmless. The takeaway is clear: If you see a spooky fog in the distance, don’t write them off as scud clouds without first triple-checking the weather forecast.
Snow squall
A snow squall sounds cozy, but it’s actually a sudden snowstorm with heavy snowfall and strong winds. Like a flash flood, a snow squall comes on fast and furious. “With a snow squall, you can go from perfectly fine visibility to not being able to see just a few feet in front of you in a matter of seconds,” Hinson says.
Hinson recommends treating every snow squall as a potentially risky situation. “If you’re on the highway and get a snow squall alert, safely pull off the road,” he says.
Weather whiplash
If you’ve ever worn shorts one day and a parka the next, you’re already familiar with this term for flip-floppy weather. Officially, weather whiplash means “sudden changes from one type of extreme weather to another, such as record cold to record heat or drought to flood,” Perry says. He notes that Nevada experienced weather whiplash in June when parts of the state went from a record heat of 96 degrees Fahrenheit on June 18, 2025, to a record low of 24 degrees Fahrenheit only a few days later on June 22.
Alas, it isn’t just an isolated climate quirk limited to one part of our country: A 2025 study published in Nature found that since 1961, 60% of the globe has been experiencing an increase in these rapid flips between hot and cold weather, and the trend will likely accelerate in the future.
Wet-bulb temperature
Wet-bulb temperature is a measure that ties together heat and humidity. “It comes from a weather instrument called a sling psychrometer,” Hinson explains. To find the wet-bulb reading, you wrap a wet muslin cloth around one of the two thermometers and swing it around above your head. “That sounds pretty crazy,” he says, “but you’re measuring the difference between the air temperature and the feels-like temperature.” It’s telling you how readily water can evaporate out of that towel that you wrapped around the thermometer.
“If we reach a wet-bulb temperature that is equal to the air temperature, it’s very, very hard for water to evaporate,” Hinson says. “This is important for us as humans because that’s how we get our heat out [through sweating].” So a high wet-bulb temperature “can be dangerous for humans because we can’t get the heat out of our bodies,” he adds.
While a high wet-bulb day is potentially hazardous to all of us, it’s especially dangerous for vulnerable groups, including older adults and children. It’s also risky for anyone working or exercising outdoors—or even indoors if they’e not in air-conditioned spaces.
About the experts
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At Reader’s Digest, we’re committed to producing high-quality content by writers with expertise and experience in their field in consultation with relevant, qualified experts. We rely on reputable primary sources, including government and professional organizations and academic institutions as well as our writers’ personal experiences where appropriate. For this piece on lesser-known weather terms, Lisa Lombardi tapped her experience as a longtime journalist who covers science and health for Reader’s Digest. We verify all facts and data, back them with credible sourcing and revisit them over time to ensure they remain accurate and up to date. Read more about our team, our contributors and our editorial policies.
Sources:
- Jacob Hinson, meteorologist with AccuWeather in State College, Pennsylvania; phone interview, September 8, 2025
- Baker Perry, PhD, professor of climatology at University of Nevada, Reno; email interview, September 12, 2025
- National Weather Service: “Glossary of Weather Terms”
- National Weather Service: “Thunderstorm Winds and Derechos”
- NOAA Storm Prediction Center: “About Derechos”
- University of Nebraska–Lincoln: “Husker Who Coined Flash Drought Helps Define Emerging Phenomenon”
- Colorado Geological Survey: “Debris and Mud Flows”
- Penn Today: “Strongest nor’easters getting stronger”
- National Oceanic and Atmospheric Administration: Center for Environmental Education: “Global Climate Report (August 2025)”
- NOAA: “What is the Pineapple Express?” (June 2024)
- Nature: “Rapid flips between warm and cold extremes in a warming world,” (April 2025)
